Methods of forming integrated circuit devices using cutting tools to expose metallization pads through a cap structure and related cutting devices

Abstract

A method of fabricating a semiconductor device can include providing an integrated circuit electrically coupled to a metallization pad on a semiconductor wafer, the integrated circuit and the metallization pad covered by a cap structure. A channel can be cut in a portion of the cap structure that covers the metallization pad using a cutting tool having a tip surface and a beveled side surface to expose an upper surface of the metallization pad in the channel extending in a first direction and a conductive material can be deposited in the channel to ohmically contact the upper surface of the metallization pad in the channel.

What is claimed is: 
     
       1. A method of fabricating a semiconductor device, the method comprising:
 providing an integrated circuit electrically coupled to a metallization pad on a semiconductor wafer, the integrated circuit and the metallization pad covered by a cap structure; 
 cutting a channel in a portion of the cap structure that covers the metallization pad using a cutting tool having a tip surface and a beveled side surface to expose an upper surface of the metallization pad in the channel extending in a first direction; and 
 depositing a conductive material in the channel to ohmically contact the upper surface of the metallization pad in the channel. 
 
     
     
       2. The method of  claim 1  wherein the tip surface and a portion of the beveled side surface, that is adjacent to the tip surface, form an angle in a range between about 60 degrees to about 85 degrees. 
     
     
       3. The method of  claim 2  wherein the metallization pad has a thickness in a range between about 1.5 microns to about 2 microns. 
     
     
       4. The method of  claim 3  wherein the beveled side surface forms a beveled side wall in the channel relative to the upper surface of the metallization pad. 
     
     
       5. The method of  claim 1  wherein a height of the beveled side surface is at least about 50% of a thickness of the cap structure. 
     
     
       6. The method of  claim 5  wherein a side surface of the cutting tool above the beveled side surface and the tip surface form an angle that is in a range between about 60 degrees to about 90 degrees. 
     
     
       7. The method of  claim 1  wherein the channel has a width that exposes at least about 20% of the upper surface of the metallization pad. 
     
     
       8. The method of  claim 1  wherein cutting the channel in the portion of the cap structure comprises moving the cutting tool across the semiconductor wafer within the cap structure to form the channel exposing the upper surface of the metallization pad. 
     
     
       9. The method of  claim 1  wherein the cutting tool comprises a rotating blade or a rotating wire. 
     
     
       10. The method of  claim 1  wherein a thickness of the cap structure is in a range between about 50 um to about 100 um. 
     
     
       11. The method of  claim 1  wherein the cap structure comprises glass or polymer material. 
     
     
       12. A method of fabricating a semiconductor device, the method comprising:
 providing an integrated circuit electrically coupled to a metallization pad on a semiconductor wafer, the integrated circuit and the metallization pad covered by a cap structure; 
 cutting a channel in a portion of the cap structure that covers the metallization pad using a cutting tool having a tip surface and a beveled side surface to expose an upper surface of the metallization pad in the channel extending in a first direction; and 
 depositing a conductive material in the channel to ohmically contact the upper surface of the metallization pad in the channel, wherein providing the integrated circuit electrically coupled to the metallization pad on the semiconductor wafer comprises: 
 providing the integrated circuit electrically coupled to a first metallization pad on the semiconductor wafer and a second metallization pad that is electrically coupled to the integrated circuit; and 
 wherein cutting the channel in the portion of the cap structure comprises moving the cutting tool across the semiconductor wafer in the first direction within the cap structure to form the channel exposing the upper surface of the first metallization pad and an upper surface of the second metallization pad. 
 
     
     
       13. The method of  claim 12  wherein the integrated circuit comprises a first integrated circuit, the method further comprising:
 a second integrated circuit, separated from the first integrated circuit in the first direction on the semiconductor wafer, the second integrated circuit electrically coupled to a third metallization pad, aligned to the first and second metallization pads in the first direction and covered by the cap structure, on the semiconductor wafer; and 
 wherein cutting the channel in the portion of the cap structure comprises moving the cutting tool across the semiconductor wafer in the first direction within the cap structure to form the channel exposing the upper surface of the first metallization pad, the upper surface of the second metallization pad, and the upper surface of the third metallization pad; and 
 depositing the conductive material in the channel to ohmically contact the upper surfaces of the first, second, and third metallization pads in the channel. 
 
     
     
       14. A method of fabricating a semiconductor device, the method comprising:
 providing an integrated circuit electrically coupled to a metallization pad on a semiconductor wafer, the integrated circuit and the metallization pad covered by a cap structure; 
 cutting a channel in a portion of the cap structure that covers the metallization pad using a cutting tool having a tip surface and a beveled side surface to expose an upper surface of the metallization pad in the channel extending in a first direction; and 
 depositing a conductive material in the channel to ohmically contact the upper surface of the metallization pad in the channel, wherein the integrated circuit comprises a first integrated circuit electrically coupled to the metallization pad comprising a first metallization pad and covered by the cap structure comprising a first cap structure, the method further comprising: 
 a second integrated circuit, separated from the first integrated circuit in a second direction orthogonal to the first direction on the semiconductor wafer, the second integrated circuit electrically coupled to a second metallization pad and covered by a second cap structure, on the semiconductor wafer; and 
 wherein cutting the channel in the portion of the cap structure comprises moving the cutting tool across the semiconductor wafer in the first direction within the first and second cap structures between the first and second integrated circuits to form the channel exposing the upper surface of the first metallization pad and an upper surface of the second metallization pad; and 
 depositing the conductive material in the channel to ohmically contact the upper surfaces of the first and second metallization pads in the channel. 
 
     
     
       15. The method of  claim 14  wherein the beveled side surface of the cutting tool comprises a first beveled side surface facing the first integrated circuit, the cutting tool further comprising:
 a second beveled side surface facing the second integrated circuit, wherein the tip surface extends from the first beveled side surface to the second beveled side surface. 
 
     
     
       16. The method of  claim 15  wherein the tip surface and a portion of the first beveled side surface, that is adjacent to the tip surface, form a first angle in a range between about 60 degrees to about 85 degrees and wherein the tip surface and a portion of the second beveled side surface, that is adjacent to the tip surface, form a second angle in a range between about 60 degrees to about 85 degrees. 
     
     
       17. The method of  claim 16  wherein the channel has a width that exposes at least about 20% of the upper surface of the first metallization pad and about 100% of the upper surface of the second metallization pad. 
     
     
       18. A method of fabricating a semiconductor device, the method comprising:
 providing an integrated circuit electrically coupled to a metallization pad on a semiconductor wafer, the integrated circuit and the metallization pad covered by a cap structure; 
 cutting a channel in a portion of the cap structure that covers the metallization pad using a cutting tool having a tip surface and a beveled side surface to expose an upper surface of the metallization pad in the channel extending in a first direction; and 
 depositing a conductive material in the channel to ohmically contact the upper surface of the metallization pad in the channel, wherein ohmic contact between the conductive material in the channel and the upper surface of the metallization pad a specific contact resistivity of less than about 10 e-03 ohm 2 . 
 
     
     
       19. A method of fabricating a semiconductor device, the method comprising:
 sawing a channel in a cap structure that covers a semiconductor wafer, using a cutting tool having a tip surface wide enough to expose metallization pads of two directly adjacent devices on the semiconductor wafer in a single pass and having opposing beveled side surfaces to impart a corresponding beveled side wall surface in each side of the channel adjacent to each device; and 
 depositing a conductive material in the channel to ohmically contact an upper surface of the metallization pads in the channel. 
 
     
     
       20. The method of  claim 19  wherein the corresponding beveled side wall surface in each side of the channel form an angle with a surface of the semiconductor wafer in a range between about 60 degrees to about 85 degrees. 
     
     
       21. A method of fabricating a semiconductor device, the method comprising:
 providing devices electrically coupled to metallization pads on a semiconductor wafer covered by a cap structure; and 
 sawing a channel in the cap structure that covers the semiconductor wafer using a cutting tool having a tip surface wide enough to expose a row of metallization pads of a device on the semiconductor wafer, the channel having opposing beveled side surfaces to impart a corresponding beveled side wall surface in each side of the channel, wherein the corresponding beveled side wall surface in each side of the channel form an angle with a surface of the semiconductor wafer in a range between about 60 degrees to about 85 degrees.